The present invention relates generally to inkjet printheads, and more particularly to a wide-array inkjet printhead assembly.
A conventional inkjet printing system includes a printhead, an ink supply which supplies liquid ink to the printhead, and an electronic controller which controls the printhead. The printhead ejects ink drops through a plurality of orifices or nozzles and toward a print medium, such as a sheet of paper, so as to print onto the print medium. Typically, the orifices are arranged in one or more arrays such that properly sequenced ejection of ink from the orifices causes characters or other images to be printed upon the print medium as the printhead and the print medium are moved relative to each other.
In one arrangement, commonly referred to as a wide-array inkjet printing system, a plurality of individual printheads, also referred to as printhead dies, are mounted on a single carrier. As such, a number of nozzles and, therefore, an overall number of ink drops which can be ejected per second is increased. Since the overall number of drops which can be ejected per second is increased, printing speed can be increased with the wide-array inkjet printing system.
Mounting a plurality of printhead dies on a single carrier, however, requires a plurality of power, ground, and data lines for the printhead dies. As such, the single carrier must accommodate a plurality of electrical connections between the electronic controller and each of the printhead dies. Since each printhead die typically requires multiple electrical connections, any difficulty in completing such connections is compounded by the number of printhead dies.
Accordingly, a need exists for routing power, ground, and data lines between an electronic controller and a plurality of printhead dies mounted on a single carrier. More particularly, a need exist for facilitating the numerous electrical connections required by the plurality of printhead dies.
One aspect of the present invention provides an inkjet printhead assembly. The inkjet printhead assembly includes a carrier having a first side and a second side contiguous with the first side, a plurality of printhead dies each mounted on the first side of the carrier, an electrical circuit disposed on the first side and the second side of the carrier, and a plurality of electrical connectors each electrically coupled to the electrical circuit and one of the printhead dies.
In one embodiment, the electrical circuit includes a flexible electrical circuit. In one embodiment, the flexible electrical circuit includes a plurality of conductive paths provided in a layer of flexible material. In one embodiment, the layer of flexible material has a plurality of openings defined therein, each of the openings accommodating one of the printhead dies.
In one embodiment, the flexible electrical circuit includes a first portion disposed on the first side of the carrier and a second portion disposed on the second side of the carrier, the first portion including a first plurality of electrical contacts and the second portion including a second plurality of electrical contacts, wherein at least one of the conductive paths of the flexible electrical circuit extends between at least one of the first plurality of electrical contacts and at least one of the second plurality of electrical contacts.
In one embodiment, the conductive paths include at least one power path, at least one ground path, and at least one data path.
In one embodiment, the carrier has a plurality of ink passages defined therein, at least one of the ink passages communicating with the first side of the carrier and at least one of the printhead dies.
In one embodiment, the second side of the carrier is substantially perpendicular to the first side of the carrier.
In one embodiment, the electrical circuit includes a first interface disposed on the first side of the carrier, each of the electrical connectors being electrically coupled to the first interface. In one embodiment, the first interface includes a plurality of electrical contacts, wherein each of the printhead dies includes at least one electrical contact, and wherein each of the electrical connectors is electrically coupled to one of the electrical contacts of the first interface and the at least one electrical contact of one of the printhead dies.
In one embodiment, each of the electrical connectors includes a wire lead having a first end electrically coupled to one of the electrical contacts of the first interface and a second end electrically coupled to the at least one electrical contact of one of the printhead dies.
In one embodiment, the electrical circuit includes a second interface disposed on the second side of the carrier, the second interface defining at least one electrical interconnect of the inkjet printhead assembly.
Another aspect of the present invention provides a method of forming an inkjet printhead assembly. The method includes providing a carrier having a first side and a second side contiguous with the first side, mounting a plurality of printhead dies on the first side of the carrier, disposing an electrical circuit on the first side and the second side of the carrier, and electrically coupling a plurality of electrical connectors with the electrical circuit and the printhead dies.
The present invention provides an electrical circuit which facilitates electrical routing between an electronic controller and a plurality of printhead dies each mounted on a single carrier.